On May 13, 2026, between 14:31 and 16:03 UTC, the Code Scanning service experienced processing delays and 12% of check runs took over 15 minutes to complete. The delays were caused by replication lag due to an internal database migration, resulting in insufficient worker capacity for our high rate of job enqueues.

We mitigated the impact by scaling our processing workers by 34%. Code Scanning results returned to normal processing times after the mitigation was applied.

The capacity increases are permanent, and we are looking into more ways to decrease the load on our workers to help prevent this in the future.

Posted May 13, 2026 - 16:03 UTC

CodeQL impact has been mitigated. We are continuing to monitor for durable recovery.

Posted May 13, 2026 - 15:30 UTC

The degradation has been mitigated. We are monitoring to ensure stability.

Posted May 13, 2026 - 15:26 UTC

We have applied a mitigation to increase processing capacity. We are continuing to monitor to confirm full recovery. We will provide another update by 15:30 UTC.

Posted May 13, 2026 - 14:58 UTC

We are investigating delays affecting CodeQL, the code analysis engine used by Code Scanning. Some users may experience delayed or incomplete code scanning results. Our engineering team is investigating. We will provide another update by 15:15 UTC.

Posted May 13, 2026 - 14:43 UTC

We are investigating reports of impacted performance for some GitHub services.

Posted May 13, 2026 - 14:41 UTC